Re: More on unique vs distinct

Not 100% sure....

select count(*) from (select distinct source_id from obis_sources) t

Wm.A.Stafford wrote:
> I guess I should have been a bit more specific. Here is an example of
> the type of query I'm finding in the Oracle app and the results of my
> attempt to find a PostgreSQL equivalent.
>
> select count(unique 'source_id') from obis_sources;
> pgAdmin III query responds:
> ERROR: syntax error at or near "'source_id'" at character 23
>
> select count(distinct 'source_id') from obis_sources;
> pgAdmin III query responds:
> ERROR: could not identify an equality operator for type "unknown"
>
> Thanks for all the help,
> -=bill
>
>
>
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